hey, i have a 90 sunbird w/ 2.0L. the coolant gauge stays barely above the lowest number, but i know the engine is pretty hot, cause the cabin blower blows REALLY hot. the cooling fans dont turn on (presumably because the computer thinks its still cold). can anyone tell me why this might be happening? i thought stuck thermostat, but the coolant sensor is on the engine side of the thermostat, so you would think if it were stuck, the temp on the gauge would go way up...
First if the thermostat was stuck the car would engage the fan to cool it alot.That's not the case tho,so what u have is ur temp gauge is reading say 100' when it should read say 185-195 which is normal oper temp.Since this is the case just take the wire for the temp sender for the gauge itself and ground it to bare metal.IF it makes the gauge go all the way to the right or extremely hot u have a bad sending unit for the gauge.If the gauge goes to zero degrees its the gauge itself that is defective.More than likely u have a bad sending unit for the gauge,nine out of ten times its this.Even if u have replaced that recently does not mean it can not be a bad part,just try the above method it is 100% sure way to verify the problem,I know I have lots and lots of electr exper and unless u have a short in ur wiring this should answer ur problem.
replace your coolant temp sensor(s)
-Borsty
i just replaced the coolant temp sensor like a week ago... same problem :-(
Did u do the check like I said in my previous post?Tends to make think as long as u are using the stock gauge it's the gauge is the problem here.U need to do a continuity check on the temp sending wiring to ensure the gauge is getting a reading.Black is ur ground wire and yellow is the ect sensor wire,where it gets a reading.Use a multimeter and use the black prong on ur multi to grd and the red touch the sending unit wire with it unconnected from the sender if it beeps,assumming ur multimeter will do this u hv a good connection from the sender to the gauge.If not on the sound just chk it with it connected to the sender turn the key on,not running u should have voltage showing on ur meter in ohms,or volts prolly ohms on resistance.Ok hope this makes sense and let us know ur findings
This is why BORSTY put the (S) after sender
My 93 Cav (My info is only up to 94) has TWO sensors and I think yours has also.
There are TWO separate circuits
(1) The Engine Coolant Temperature SENDER has a Dark Green or Dark Green /White wire and operates solely the Temp Gauge.
(2) The Engine Coolant Temperature SENSOR has a Yellow SIGNAL and a Black ground wire and feeds directly to the ECM.
This circuit controls the fan
This is just some info and not a direct answer to your problem
Hope this helps
Alont
Could you have air in the system which just needs bleeding?
How is your coolant level when all this is going on?
Just some thoughts
Alont
D M wrote:i just replaced the coolant temp sensor like a week ago... same problem :-(
u can at least 2 maybe 3.
my 305 TBI had 3.
-Borsty
